: _shift? ( kc -- f ) DUP 0x12 = SWAP 0x59 = OR ;
: _get ( -- kc ) 0 ( dummy ) BEGIN DROP (ps2kc) DUP UNTIL ;
: (key) _get
    DUP 0xe0 ( extended ) = IF ( ignore ) DROP (key) EXIT THEN
    DUP 0xf0 ( break ) = IF DROP ( )
        ( get next kc and see if it's a shift )
        _get _shift? IF ( drop shift ) 0 PS2_SHIFT C! THEN
        ( whether we had a shift or not, we return the next )
        (key) EXIT THEN
    DUP 0x7f > IF DROP (key) EXIT THEN
    DUP _shift? IF DROP 1 PS2_SHIFT C! (key) EXIT THEN
    ( ah, finally, we have a gentle run-of-the-mill KC )
    PS2_CODES PS2_SHIFT C@ IF 0x80 + THEN + C@
    ?DUP NOT IF (key) THEN ;